![Maxim Integrated MAX31782 Скачать руководство пользователя страница 126](http://html1.mh-extra.com/html/maxim-integrated/max31782/max31782_user-manual_1744481126.webp)
MaximIntegrated 15-2
MAX31782 User’s Guide
Revision 0; 8/11
SECTION 15: WATCHDOG TIMER
The watchdog timer is a user-programmable clock counter that can serve as a time-base generator, an event timer, or
a system supervisor . As shown in
, the timer is driven by the main system clock and is supplied to a series
of dividers . If the watchdog interrupt and the watchdog reset are disabled (WDCN .EWDI = 0 and WDCN .EWT = 0), the
watchdog timer and its input clock are disabled . Whenever the watchdog timer is disabled, the watchdog interval timer
(per WDCN .WD[1:0] bits) and 512 clock reset counter are reset if either the interrupt or reset function is enabled . When
the watchdog timer is initially enabled, there is a one-clock to three-clock-cycle delay before it starts . The divider output
is selectable, and determines the interval between timeouts . When the timeout is reached, an interrupt flag is set, and
if enabled, an interrupt occurs . A watchdog-reset function is also provided in addition to the watchdog interrupt . The
reset and interrupt are completely discrete functions that can be acknowledged or ignored, together or separately for
various applications .
Figure 15-1. Watchdog Timer Block Diagram
SYSTEM
CLOCK
TIMEOUT INTERVAL SELECTOR
WD1
WD0
DIVIDE BY
2
12
DIVIDE BY
2
3
2
12
2
15
2
18
2
21
DIVIDE BY
2
3
WDIF
WTRF
WATCHDOG
INTERRUPT
EWT
(ENABLE WATCHDOG TIMER RESET)
EWDI
(ENABLE WATCHDOG INTERRUPT)
RESET COUNTER
512 SYSCLK DELAY
DIVIDE BY
2
3
RWT
(RESET WATCHDOG)
TIMEOUT
RESET
MAX31782